Britain will witness the biggest strikes by public sector workers in decades if the government does not relent on its scheme to reform pension plans, cut jobs and reduce salaries, UK unions have warned.

Union leaders claim that at least 1-million state workers could walk out on their jobs this fall, if the coalition government of Prime Minister David Cameron continues to press on with its reform proposals.

Dave Prentis, the General Secretary of UNISON, the U.K.’s largest public sector union, further warned the industrial unrest could last for months.

Prentis has told media that he believes that public sector workers in Britain could see their wages reduced by as much as 10 percent as a result of pension contribution increased changes and salary freezes.

Ahead of Unison’s annual conference next week, Prentis wanted the government is now on a collision course with public sector unions over pensions.

It is very clear we are on a collision course unless the Government changes its policies,” he told British media.

If we are prevented from reaching agreement we will move to a ballot in the summer or early autumn. It will not be one day of action - it will be long term industrial action throughout all our public services to prevent destruction of our pension schemes.”

Prentis added:“Be in no doubt this union is on the road to industrial action in the autumn. This will not be a one-day action as we know that will not change anything. his is longer term industrial action to prevent the destruction of public service pension schemes.” Moreover, Unison estimates that 40 percent of public sector employees may consider leaving their pension plans because of the higher contributions costs demanded by the government.

“These measures are not even going to sustain our pension schemes,” Prentis said.

“This is a coalition which is hell bent on making employees in the public services pay for the failure of bankers.”

Unison also said it believes that over the next three years, 500,000 local authority posts will be eliminated, as will 600,000 other private sector jobs.

The union also said that more than 66,000 council jobs have already vanished, with an additional 172,000 at the risk of being cut.

Similarly, other prominent unions, including the Association of Teachers and Lecturers (ATL) and the National Union of Teachers (NUT) are also reportedly considering strike actions to protests the government’s actions. These teacher unions are currently balloting their members (who number some 300,000) on the strike action.

According to reports, the ATL has never before engaged in a ATL general secretary Mary Bousted said members are heavily in favor of the strike.

I've never seen ATL members so angry about what the Government is doing and I've never seen such determination by members to protect their pensions, she said.

[Pensions] are a modest return for a lifetime of teaching the nation's children.

Similarly, Christine Blower, the NUT general secretary, told media: Teachers of all ages are astonished that the Government should be doing this to their pensions.

Meanwhile, the government is reportedly considering new anti-strike legislation to prevent such industrial actions.